1. Field of the Invention
The invention relates to drive belt loading systems and to magnetic disk drives employing such systems.
2. Description of the Prior Art
A drive belt loading system for use in a magnetic disk file is shown in FIGS. 2A and 2B of U.S. Pat. No. 3,786,454 to Lissner and Mulvany. In that patent a pair of spring biased idler arms are employed in a disk drive to splay apart a drive belt and enable the receipt of a data module pulley within the loop formed by the belt. A loading mechanism moves the data module so that its pulley contacts the belt and overcomes the action of the idler arms which are then pivoted inwardly. Loading motion of the module also moves a belt drive motor, mounted on a pivot plate, against a spring bias. A cam on the pivot plate strikes the idler arms and forces them to a position out of contact with the belt. Reversal of the above procedure unloads the belt and permits removal of the module. The Lissner and Mulvany arrangement requires both motion of the module and the drive motor to effect loading and is relatively complex.
United Kingdom Pat. No. 593,780 shows an arrangement for coupling two horizontal shafts for co-rotation by means of a belt. The belt is placed on an idler pulley on one shaft and is manually shifted from a perch to a conical portion of a pulley fixed to a second shaft. Rotation of the shaft causes the belt to climb the conical portion of the second shaft pulley and at the same time to transfer from the first shaft idler pulley to an adjacent pulley fixed to the first shaft. Thus the two shafts are coupled for rotation together. However, this coupling is not automatic and neither shaft is part of a removable device.